From: Avi Kivity <avi@redhat.com>
Date: Thu, 31 Mar 2011 18:58:55 +0000 (-0700)
Subject: KVM: i8259: initialize isr_ack
X-Git-Tag: v2.6.35.12~6
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a0e696446fddddabf00c57e1db5f38b929c3e713;p=thirdparty%2Fkernel%2Fstable.git

KVM: i8259: initialize isr_ack

commit a0272630bb594b4eac03a79e77957df7dad8eade upstream.

isr_ack is never initialized.  So, until the first PIC reset, interrupts
may fail to be injected.  This can cause Windows XP to fail to boot, as
reported in the fallout from the fix to
https://bugzilla.kernel.org/show_bug.cgi?id=21962.

Reported-and-tested-by: Nicolas Prochazka <prochazka.nicolas@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---

diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 93825ff3338fa..8a3324668cac0 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -553,6 +553,8 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)
 	s->irq_request_opaque = kvm;
 	s->pics[0].pics_state = s;
 	s->pics[1].pics_state = s;
+	s->pics[0].isr_ack = 0xff;
+	s->pics[1].isr_ack = 0xff;
 
 	/*
 	 * Initialize PIO device